It is common practice to provide, for example in supermarkets and other retail outlets or at work stations, dispensers for dispensing pre-formed bags or sheets at points of use. One such dispenser holds a roll of bags pre-formed along the length of the roll, the bags being obtainable from the dispenser by pulling each bag and tearing it from the roll along a perforated strip. Such a dispenser when loaded with a full roll is bulky and it can be difficult to remove the individual bags. These problems also arise with rolls of sheets having perforated strips between individual sheets. As an alternative to rolls, stacks of individual pre-formed bags or sheets are available from which it is a simpler task to remove and open individual bags or sheets. The present invention is concerned with a dispenser for such stacks of individual pre-formed bags or sheets.